Hooktheory Book1 Web Page Show nothing

I just buy Hooktheory I Web Version.
when I go to http://www.hooktheory.com/music-theory-for-songwriting/outline, the page show normally. (a content list)
But no matter what item I click in this page, I was referred to the url http://www.hooktheory.com/book1/app, and nothing shows in the web page.

I use the safari’s develop tool , it produce an error when loading resources:
“Can’t find variable: PitchPlayer”
which is caused by a syntax error in libs-and-custom.min.js (Invalid regular expression: unmatched parentheses)。
I don’t know much about js. just to describe my situation.

is there something wrong with the js code? or compatibility error with my browser?

My Computer OS is Mac OS 10.11.4.
The Browser I used is Chrome 48.0.2564.116 and Safari 9.1 (11601.5.17.1). (both do not work, the same phenomenon)

Still not work. Can anybody help me?

I download the latest Firefox. and still not work!!!

After Change the chrome settings to force the web page use utf-8 encoding format, it seems solve my problem.
It seems your js code has some no-ascii character, and you guys should repair it because all the internet explorer in China use GBK as the default encoding. (And I think it may also happen in some other country like Japan, Korea etc.)

We’re working on a solution to this so you don’t have to manually make this change. I will post here when it is fixed. Thanks again for the good debugging.

EDIT: this has been fixed. Let me know if that doesn’t work for you

-Dave

it works for me! the problem has disappeared.

Thank you !!